Waist support structure of seat back

ABSTRACT

Disclosed is a waist support structure of a seat back. The seat back includes a first frame, a second frame coupled to the first frame, and a net member mounted between the first and second frames. The second frame includes a mounting brace mounted thereto and the mounting brace include a waist support coupling section that is connectable with a waist support. The waist support includes a support portion including a rigid plate and a connection portion. The support portion includes a barrel mounted thereto and extending toward the connection portion. The connection portion includes a projection peg mounted thereto and extending toward the support portion to correspond to the barrel. An elastic element has an end fit to the projection peg of the connection portion and an opposite end fit in the barrel of the support portion so as to interface between the connection portion and the support portion.

(a) TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to a waist support structure of a seat back, and more particularly to a waist support of a seat back that helps improves a supporting force and comfortableness and thus enhances the performance of the waist support.

(b) DESCRIPTION OF THE PRIOR ART

To make the waist of a user sitting on a seat properly supported so as to provide the user with comfortable perception of sitting on the seat, a waist support is often attached to the back of the seat. Taking a net seat back as an example, a waist support may be provided on the backside of the net that constitutes primarily the seat back.

As shown in FIGS. 1 and 2, a seat back 1 comprises a first frame 11, a second frame 12 corresponding to and coupled to the first frame 11, and a net member 13 mounted between the first frame 11 and the second frame 12.

As shown in FIG. 1, the second frame 12 comprises a mounting brace 121. The mounting brace 121 comprises an insertion rib 122. The insertion rib 122 receives a waist support 2 to be fit thereon. The waist support 2 comprises an insertion portion 21, and the insertion portion 21 is provided, on a side thereof facing the net member 13, with a soft support portion 22. The insertion portion 21 comprises an insertion slot 211. The insertion slot 211 is fit over the insertion rib 122 to mount the waist support 2 on the mounting brace 121 of the second frame 12. The support portion 22 functions to support the waist of a user sitting on the seat.

As shown in FIG. 2, a conventional net seat back 1 is provided with the above-described structure of waist support 2, so as to use the soft support portion 22 of the waist support 2 to support the waist of the user. However, since the conventional support portion 22 of the waist support 2 is soft and is often formed of sponge or a foamed material, the weights of the user and the waist support 2 must be supported by the sponge material of the support portion 22 and this often lead to insufficiency of supporting force. Specifically speaking, the support portion 22 is either too soft to provide sufficient supporting power or too stiff to provide over supporting, both cases being uncomfortable to the waist of the user.

Thus, it is a challenge of the chair manufacturers to provide a waist support structure of a seat back to overcome the deficiency of the conventional waist support.

SUMMARY OF THE INVENTION

The primary object of the present invention is to provide a waist support structure of a seat back that overcome the deficiency of known waist support structures of seat backs in respect of comfortableness and supporting capability.

In this respect, a major technical solution presented in claim 1 of the present invention is to provide a waist support structure of a seat back, wherein the seat back comprises a first frame, a second frame corresponding to and coupled to the first frame, and a net member mounted between the first frame and the second frame, the second frame comprising a mounting brace mounted thereto, the mounting brace comprising a waist support coupling section mounted thereto, the waist support coupling section being connectable with a waist support, wherein the waist support comprises a support portion and a connection portion; the support portion comprises a plate, the support portion comprising at least one barrel mounted thereto and extending toward the connection portion, the connection portion comprising at least one projection peg mounted thereto and extending toward the support portion, the projection peg and the barrel being arranged to correspond to each other, the connection portion and the support portion comprising at least one elastic element supported and interfacing therebetween, the elastic element having an end fit to the projection peg of the connection portion, the elastic element also having an opposite end fit in the barrel of the support portion.

The efficacy that the major technical solution of claim 1 of the present invention may achieve is that a waist support coupling section is provided on a second frame for coupling with a waist support and the waist support comprises a support portion and a connection portion with elastic element connected and interfacing between the connection portion and the support portion, whereby the support portion is movable, through expansion and contraction, with respect to the connection portion by means of the elasticity of the elastic elements. When the support portion is depressed, the depressing force can be absorbed by the elastic elements and a supporting force acting on or induced on the support portion is taken by or born on the elastic elements so that the support portion may show a sufficient supporting force thereby improving the performance of the waist support of the seat back.

The foregoing objectives and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts.

Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view showing a conventional waist support of a seat back.

FIG. 2 is a perspective view showing the conventional waist support of the seat back.

FIG. 3 is an exploded view showing a waist support of a seat back according to the present invention.

FIG. 3A is an enlarged view of a circled portion of FIG. 3.

FIG. 4 is a perspective view showing the waist support of the seat back according to the present invention.

FIG. 5 is a cross-sectional view showing a portion of the waist support of the seat back according to the present invention.

FIG. 6 is a schematic view showing a height-adjusting operation of the waist support of the seat back according to the present invention.

FIG. 7 is a schematic view showing an operation of the waist support of the seat back according to the present invention after being depressed

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following descriptions are exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims.

Firstly, referring to FIGS. 3 and 4, the present invention provides a waist support structure of a seat back. The seat back 3 comprises a first frame 4, a second frame 5 corresponding to the first frame 4 and combinable with the first frame 4, and a net member 6 arranged between the first frame 4 and the second frame 5.

As shown in FIGS. 3 and 4, the first frame 4 is made in the form of a surrounding frame having a hollowed central portion, and the first frame 4 also has a circumferential portion that is provided with a recessed groove 41 circumferentially extending along the circumferential portion. The recessed groove 41 is provided for fixing the net member 6.

As shown in FIGS. 3, 3A, and 4, the second frame 5 is made in the form of a surrounding frame having a hollowed central portion. The second frame 5 is provided with a mounting brace 51 in a lower part of the central portion. The second frame 5 also has a circumferential portion that is recessed to form a circumferentially extending insertion groove 52 such that the insertion groove 52 of the second frame 5 receives the circumferential portion of the first frame member 4 to be inserted therein whereby the first frame 4 is fit into the insertion groove 52 of the second frame 5. The mounting brace 51 is provided, at a location around a middle thereof, with a waist support coupling section 53. The waist support coupling section 53 comprises an insertion rib 531 and an adjustment toothed rack section 532 mounted on the insertion rib 531. The insertion rib 531 comprises an upper stop section 5311 and a lower stop section 5312. The upper stop section 5311 is in the form of an elastically deformable barb. The waist support coupling section 53 is provided for mounting and supporting a waist support 7.

As shown in FIG. 4, the net member 6 is fixed to the first frame 4 by being fastened by fasteners, such as nails or staples (not shown).

As shown in FIGS. 3, 4, and 5, the waist support 7 comprises a support portion 71 and a connection portion 72. The support portion 71 is a curved plate. The support portion 71 comprises a plurality of barrels 711 mounted thereto and extending toward the connection portion 72. An illustrative example of two barrels 711 is shown for embodying the present invention. The barrels 711 are arranged at locations that are respectively on left and right halves and are opposite to each other. Each of the barrels 711 comprises a fastening hole 712 formed therein. The connection portion 72 comprises a plurality of projection pegs 721 mounted thereto and extending toward the support portion 71. The projection pegs 721 are arranged to respectively correspond to the barrels 711. The projection pegs 721 have an outside diameter that is smaller than an inside diameter of the barrels 711 so as to allow the projection pegs 721 to be respectively received into the barrels 711. The connection portion 72 is provided with a plurality of through holes 7211 respectively corresponding to the fastening holes 712 of the support portion 71. The through holes 7211 extend through the projection peg 721 so as to receive the extension of a fastening element S through the through hole 7211 to fixe the connection portion 72 to the support portion 71. The connection portion 72 is provided with a receiving channel 722 facing the waist support coupling section 53 of the second frame 5. The receiving channel 722 is formed of two C-shaped channel members forming recessed grooves facing each other. The receiving channel 722 is fit over the insertion rib 531 of the waist support coupling section 53 of the second frame 5. The receiving channel 722 is provided, at an upper end thereof, with two stop blocks 723 respectively located at left and right sides. The receiving channel 722 is provided, at a lower end thereof, with an adjustment block 724. Each of the projection pegs 721 of the connection portion 72 receives an elastic element 73 fit thereon to encompass it. The elastic element 73 has an opposite distal end that is fit into the corresponding barrel 711 of the support portion 71. In other words, a plurality of elastic elements 73 is arranged and interfaced between the connection portion 72 and the support portion 71. The end of the elastic element 73 that is received in and located in the barrel 711 of the support portion 71 is positioned and retained by the barrel 711 of the support portion 71. An end of the elastic element 73 that is fit over the projection peg 721 of the connection portion 72 is retained in positioned by the projection peg 721 of the connection portion 72. In this way, the elastic elements 73 are securely supported between the connection portion 72 and the support portion 71 and thus, the support portion 71 is made movable, for expansion and contraction, with respect to the connection portion 72 by means of the elasticity of the elastic elements 73. More specifically, when the support portion 71 is depressed, the depressing force can be absorbed by the elastic elements 73 and a supporting force acting on or induced on the support portion 71 is taken by or born on the elastic elements 73 so that the support portion 71 may show a sufficient supporting force. Further, due to the outside diameter of the projection pegs 721 being smaller than the inside diameter of the barrels 711, when the projection pegs 721 are received into the barrels 711, a predetermined gap is present between the projection pegs 721 and the barrels 711, which in combination with rotatabiltiy and movability of the elastic element 73 in a directionless manner, allows for omnidirectional minute adjustment of the support portion 71.

As shown in FIGS. 3, 5, and 6, the stop blocks 723 of the receiving channel 722 are arranged to get into contact engagement with and thus stopped by the upper stop section 5311 or the lower stop section 5312 of the insertion rib 531 of the second frame 5 during a movement of the waist support with respect to the second frame of the seat back so as to prevent the waist support 7 from readily separating from the waist support coupling section 53 of the second frame 5. The adjustment block 724 that is located at a lower end of the receiving channel 722 is engageable with the adjustment toothed rack section 532 of the waist support coupling section 53 of the second frame 5 for movement and adjustment of the height of the waist support 7 with respect to the second frame 5 and to be retained at such a height.

As shown in FIGS. 4, 5, 6, and 7, in the embodiment of the seat back 3 according to the present invention, the vertical location or height of the waist support 7 relative to the second frame 5 is first adjusted by means of the connection portion 72 to suit a user so that when the user sits on the seat with the back resting on the seat back 3, the waist of the user is positioned against the waist support 7. A force is applied from the user (specifically the back of the user) to the support portion 71 of the waist support 7 and such a force is absorbed by the elastic elements 73. Due to the support portion 71 being in the form of a plate that is rigid, the support portion 71 that is set in contact with the waist of the user is generally a rigid support portion 71 that provide a sufficient supporting force to the waist of the user. On the other hand, the elastic elements 73 may absorb the force induced by the body weight of the user so that the user may be properly supported but in a comfortable manner thereby improving the performance of the waist support 7 of the seat back 3.

The efficacy of the present invention is that a waist support coupling section 53 is provided on a second frame 5 for coupling with a waist support 7 and the waist support 7 comprises a support portion 71 and a connection portion 72 with a plurality of elastic elements 73 connected and interfacing between the connection portion 72 and the support portion 71, where each elastic element 73 has an outer end that is received in a barrel 711 of the support portion 71 to be positioned in and retained in the barrel 711 of the support portion 71 and the elastic element 73 has an inner end that is fit over a projection peg 721 of the connection portion 72 to be retained in position by the projection peg 721 of the connection portion 72, so that the elastic elements 73 are securely supported between the connection portion 72 and the support portion 71, whereby the support portion 71 is movable, through expansion and contraction, with respect to the connection portion 72 by means of the elasticity of the elastic elements 73. More specifically, when the support portion 71 is depressed, the depressing force can be absorbed by the elastic elements 73 and a supporting force acting on or induced on the support portion 71 is taken by or born on the elastic elements 73 so that the support portion 71 may show a sufficient supporting force thereby improving the performance of the waist support 7 of the seat back 3.

Another efficacy of the present invention is that the outside diameter of the projection pegs 721 is smaller than the inside diameter of the barrels 711 so that when the projection pegs 721 are received into the barrels 711, a predetermined gap is present between the projection pegs 721 and the barrels 711, which in combination with rotatabiltiy and movability of the elastic element 73 in a directionless manner, allows for omnidirectional minute adjustment of the support portion 71, thereby allowing the waist support 7 be set in contact engagement with the waist of the user in a more complying manner

It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.

While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the claims of the present invention. 

I claim:
 1. A waist support structure of a seat back, wherein the seat back comprises a first frame, a second frame corresponding to and coupled to the first frame, and a net member mounted between the first frame and the second frame, the second frame comprising a mounting brace mounted thereto, the mounting brace comprising a waist support coupling section mounted thereto, the waist support coupling section being connectable with a waist support, wherein the waist support comprises a support portion and a connection portion; the support portion comprises a plate, the support portion comprising at least one barrel mounted thereto and extending toward the connection portion, the connection portion comprising at least one projection peg mounted thereto and extending toward the support portion, the projection peg and the barrel being arranged to correspond to each other, the connection portion and the support portion comprising at least one elastic element supported and interfacing therebetween, the elastic element having an end fit to the projection peg of the connection portion, the elastic element also having an opposite end fit in the barrel of the support portion.
 2. The waist support structure of the seat back according to claim 1, wherein the waist support coupling section comprises an insertion rib and an adjustment toothed rack section mounted on the insertion rib, the insertion rib comprising an upper stop section and a lower stop section; the connection portion is provided with a receiving channel facing the waist support coupling section of the second frame, the receiving channel being fit over the insertion rib of the waist support coupling section of the second frame, the receiving channel being provided, at an upper end thereof, with stop blocks, the receiving channel being also provided, at a lower end thereof, with an adjustment block.
 3. The waist support structure of the seat back according to claim 2, wherein the upper stop section is in the form of an elastically deformable barb.
 4. The waist support structure of the seat back according to claim 2, wherein the receiving channel comprises two C-shaped channel members forming recessed groove facing each other, the receiving channel being provided with two stop blocks respectively located at left and right sides.
 5. The waist support structure of the seat back according to claim 2, wherein the stop blocks of the receiving channel are selectively engageable with and thus stopped by the upper stop section and the lower stop section of the second frame the insertion rib; and the adjustment block at the lower end of the receiving channel is engageable with the adjustment toothed rack section of the second frame the waist support coupling section.
 6. The waist support structure of the seat back according to claim 1, wherein the at least one barrel mounted to the support portion extending toward the connection portion comprises a plurality of barrels, the barrels each comprising a fastening hole formed therein; and the at least one projection peg mounted to the connection portion and extending toward the support portion comprises a plurality of projection pegs.
 7. The waist support structure of the seat back according to claim 6, wherein the plurality of barrels comprises at least two, the barrels being arranged at locations that are respectively on left and right halves and are opposite to each other, the projection pegs comprising at least two, the two projection pegs and the two barrels being arranged to respectively correspond to each other.
 8. The waist support structure of the seat back according to claim 1, wherein the barrels each comprise a fastening hole formed therein; the projection pegs has an outside diameter smaller than an inside diameter of the barrels, the connection portion comprising a through hole formed therein to correspond to the fastening hole of the support portion, the through holes extending through the projection peg, whereby a fastening element is received through the through to fix the connection portion to the support portion. 